A very unusual nimcha

[ariel]

Here it is, active rust removed, black rust left in place, protected with Renaissance wax.

This is the first one with at least 3 unusual features that I have encounered:

1. All-metal handle of unusual configuration.
2. Spanish cavalry blade 1728 pattern : notice typical hexagonal profile.
3. Leather scabbard with " Tuareg" type decor.

Any help in attributing/dating it?